My 46re transmission is not shifting into 4th at wide open throttle and even at part throttle will shift slow and

Expert:

Welcome to JustAnswer!

A Stock 46RE should shift into 4th at WOT around 105MPH.

Expert:
Is it a stock transmission?

Do you have a shift kit in it?

Expert:
Here is what happens on the 3-4 shift:

3-4 SHIFT SEQUENCE

The overdrive clutch is applied in fourth gear only. The direct clutch is applied in all ranges except fourth gear. Fourth gear overdrive range is electronically controlled and hydraulically activated. Various sensor inputs are supplied to the powertrain control module to operate the overdrive solenoid on the valve body. The solenoid contains a check ball that opens and closes a vent port in the 3-4 shift valve feed passage. The overdrive solenoid (and check ball) are not energized in first, second, third, or reverse gear. The vent port remains open, diverting line pressure from the 2-3 shift valve away from the 3-4 shift valve. The overdrive control switch must be in the ON position to transmit overdrive status to the PCM. A 3-4 upshift occurs only when the overdrive solenoid is energized by the PCM. The PCM energizes the overdrive solenoid during the 3-4 upshift. This causes the solenoid check ball to close the vent port allowing line pressure from the 2-3 shift valve to act directly on the 3-4 upshift valve. Line pressure on the 3-4 shift valve overcomes valve spring pressure moving the valve to the upshift position. This action exposes the feed passages to the 3-4 timing valve, 3-4 quick fill valve, 3-4 accumulator, and ultimately to the overdrive piston. Line pressure through the timing valve moves the overdrive piston into contact with the overdrive clutch. The direct clutch is disengaged before the overdrive clutch is engaged. The boost valve provides increased fluid apply pressure to the overdrive clutch during 3-4 upshifts, and when accelerating in fourth gear. The 3-4 accumulator cushions overdrive clutch engagement to smooth 3-4 upshifts. The accumulator is charged at the same time as apply pressure acts against the overdrive piston.

GOVERNOR PRESSURE CURVES

There are four governor pressure curves programmed into the transmission control module. The different curves allow the control module to adjust governor pressure for varying conditions. One curve is used for operation when fluid temperature is at, or below, 1°C (30°F) A second curve is used when fluid temperature is at, or above, 10°C (50°F) during normal city or highway driving. A third curve is used during wide-open throttle operation. The fourth curve is used when driving with the transfer case in low range.

The PCM is in charge of shifting into 4th under WOT. Is the SCT flash tuned to allow the transmission to shift into 4th at WOT?

Expert:
Yes, it could be the Plug because it is the main harness to the transmission. The leak is most likely the front pump seal and it will not cause any shifting issues unless it leaks out so much fluid it starves the pump from oil. I would wait and see what the tuner guys say, as I'm sure they have run into this before.

Let me know if you need anymore assistance.

Expert:
The harness looks like this on the valvebody:


It bolt's on with 1 bolt and sticks through the case.. The connector looks like this:


It clips onto the internal wiring with 2 clips on each side.. If the clips are broke you will need to replace the connector.. If it's not sticking up into the case you will need to remove the valvebody and place the connector in the correct position and bolt it down so it will stick up in the case.. It is supposed to stick out this far:

Expert:
Ok, that would mean that the blue rubber weather seal on the connector is damaged, or there is dirt in the connector. It should go all the way down and clip on each side. Try and spray the connector out with brake cleaner or compressed air, and see if you can get it to clip good.

Hope that helps!

Expert:

Here is a wiring diagram:


I don't think the battery issue will affect the 3-4 shift at WOT. But if you want to verify the wiring is good, you will need to ohm Ω each one from the connector to the PCM.. If all ohm below 5Ω then wires are good.